Dynamical Tuning of the Initial Condition for New Inflation in Supergravity
نویسنده
چکیده
We point out that for a class of ‘new inflation’ models in supergravity the required initial value of the inflaton field is dynamically set if there is another inflation (‘pre-inflation’) before the ‘new inflation’. We study the dynamics of both inflatons by taking a hybrid inflation model for the ‘pre-inflation’ as an example. We find out that our ‘new inflation’ model provides reheating temperatures TR ≃ 10MeV − 104GeV low enough to avoid the gravitino problem even in gauge-mediated supersymmetry-breaking models. We also construct a model where the scale for the ‘new inflation’ is generated by nonperturbative dynamics of a supersymmetric gauge theory.
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